scholarly journals Spectroscopic and computational studies of nitrile hydratase: insights into geometric and electronic structure and the mechanism of amide synthesis

2015 ◽  
Vol 6 (11) ◽  
pp. 6280-6294 ◽  
Author(s):  
Kenneth M. Light ◽  
Yasuaki Yamanaka ◽  
Masafumi Odaka ◽  
Edward I. Solomon
Keyword(s):  
Electronic Structure ◽  
Nitrile Hydratase ◽  
Computational Studies ◽  
Amide Synthesis

In addition to its activation of coordinated nitriles, nitrile hydratase utilizes a coordinated sulfenate ligand as a well-oriented nucleophile to form a five-membered intermediate which subsequently undergoes attack by H2O to ultimately form the amide product.

Sulfonamide vs. sulfonimide: tautomerism and electronic structure analysis of N-heterocyclic arenesulfonamides

2017 ◽  
Vol 41 (16) ◽  
pp. 8118-8129 ◽  
Author(s):  
Sumit S. Chourasiya ◽  
Dhara R. Patel ◽  
C. M. Nagaraja ◽  
Asit K. Chakraborti ◽  
Prasad V. Bharatam
Keyword(s):  
Electronic Structure ◽  
Structure Analysis ◽  
Computational Studies

Experimental and computational studies suggest a preference toward the sulfonimide tautomer in N-heterocyclic arenesulfonamide.

scholarly journals Imido Cobalt Complexes with Imidyl Character

2021 ◽  
Author(s):  
alexander Reckziegel ◽  
Manjinder Kour ◽  
Beatrice Battistella ◽  
Stefan Mebs ◽  
Katrin Beuthert ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Spin Density ◽  
High Spin ◽  
Bond Activation ◽  
High Spin State ◽  
Cobalt Complexes ◽  
Spectroscopic Methods ◽  
Computational Studies ◽  
Ancillary Ligand ◽  
Unpaired Spin

We report on the synthesis of a variety of trigonal imido cobalt complexes [Co(NAryl)L<sub>2</sub>)<sup>–</sup>, (L = N(Dipp)SiMe<sub>3</sub>), Dipp = 2,6-diisopropylphenyl) bearing very long Co–NAryl bonds of around 1.75 Å. The electronic structure was interrogated using a variety of physical and spectroscopic methods indicating the first authenticated examples of cobalt bound imidyl species. Computational studies corroborate these findings and reveal that the high-spin state of these complexes gives rise to unpaired spin-density on the imide nitrogen and leads to its imidyl character. Obtained complexes are capable of intermolecular H atom abstraction from C–H bonds that yields the corresponding cobalt amides. Exchange of the Dipp-substituent on the imide by the smaller mesityl function (2,4,6-trimethylphenyl) effectuates the unexpected Me<sub>3</sub>Si shift from the ancillary ligand set to the imide nitrogen, followed by intramolecular C–H bond activation.<br>

Spectroscopic and Computational Studies of Ni Superoxide Dismutase:  Electronic Structure Contributions to Enzymatic Function

2005 ◽  
Vol 127 (15) ◽  
pp. 5449-5462 ◽  
Author(s):  
Adam T. Fiedler ◽  
Peter A. Bryngelson ◽  
Michael J. Maroney ◽  
Thomas C. Brunold
Keyword(s):  
Superoxide Dismutase ◽  
Electronic Structure ◽  
Computational Studies ◽  
Enzymatic Function

Electronic Structure of Muonated La2CuO4

2015 ◽  
Vol 827 ◽  
pp. 240-242 ◽  
Author(s):  
Ainul Fauzeeha Rozlan ◽  
Shukri Sulaiman ◽  
M.I. Mohamed-Ibrahim ◽  
Isao Watanabe
Keyword(s):  
Electronic Structure ◽  
Spin Density ◽  
Molecular Orbital ◽  
Effective Charge ◽  
The Other ◽  
Cluster Method ◽  
Computational Studies ◽  
First Principle ◽  
Apical Oxygen ◽  
Pure System

We have performed First Principle computational studies utilizing Molecular-Orbital (MO) Cluster method to examine the electronic structure of muonated La2CuO4. Based on recent works, we investigated three suggested muon sites in La2CuO4. Two possible muon sites are located near the apical oxygen O(a), and the other one is near the planar oxygen O(p). The calculations were performed at the HF/Gen level of theory. The results of our investigation show that there is a very significant covalency effect between copper and oxygen. In the pure system, the effective charge on Cu is 0.77 while the charge on the oxygens is around –1.8. In the muonated system, the charge on Cu reduces to 0.58. The spin density at Cu is 0.78 in the pure system and becomes 0.70 when muon is added. As for the muon, the charge and spin density are +0.22 and –0.0026 respectively.

scholarly journals Imido Cobalt Complexes with Imidyl Character

2021 ◽  
Author(s):  
alexander Reckziegel ◽  
Manjinder Kour ◽  
Beatrice Battistella ◽  
Stefan Mebs ◽  
Katrin Beuthert ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Spin Density ◽  
High Spin ◽  
Bond Activation ◽  
High Spin State ◽  
Cobalt Complexes ◽  
Spectroscopic Methods ◽  
Computational Studies ◽  
Ancillary Ligand ◽  
Unpaired Spin

We report on the synthesis of a variety of trigonal imido cobalt complexes [Co(NAryl)L<sub>2</sub>)<sup>–</sup>, (L = N(Dipp)SiMe<sub>3</sub>), Dipp = 2,6-diisopropylphenyl) bearing very long Co–NAryl bonds of around 1.75 Å. The electronic structure was interrogated using a variety of physical and spectroscopic methods indicating the first authenticated examples of cobalt bound imidyl species. Computational studies corroborate these findings and reveal that the high-spin state of these complexes gives rise to unpaired spin-density on the imide nitrogen and leads to its imidyl character. Obtained complexes are capable of intermolecular H atom abstraction from C–H bonds that yields the corresponding cobalt amides. Exchange of the Dipp-substituent on the imide by the smaller mesityl function (2,4,6-trimethylphenyl) effectuates the unexpected Me<sub>3</sub>Si shift from the ancillary ligand set to the imide nitrogen, followed by intramolecular C–H bond activation.<br>

Isolating key reaction energetics and thermodynamic properties during hardwood model lignin pyrolysis

2021 ◽  
Author(s):  
Tanzina Azad ◽  
Hazl F Torres ◽  
Maria Lujan Auad ◽  
Thomas Elder ◽  
Andrew J Adamczyk
Keyword(s):  
Electronic Structure ◽  
Thermodynamic Properties ◽  
Current Work ◽  
Computational Studies ◽  
Electronic Structure Methods

Computational studies on the pyrolysis of lignin using electronic structure methods have been largely limited to dimeric or trimeric models. In the current work we have modeled a lignin oligomer...

Sign in / Sign up

Export Citation Format

Share Document